Alert archive / Wisconsin

Weather alerts in Milwaukee County, Wisconsin

2,750 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Milwaukee County and its neighbors

Each county as a circle sized by its count since 1986. Tap one for its archive.

Alerts
2,750
Warnings
634
Watches
443
Advisories
861
Busiest year
2008179 alerts
Average year
67over 41 years on file

Over time

By year

Before late 2005 the archive holds only tornado, severe thunderstorm, flash flood and marine warnings, and from 1997 SPC's watches, so the jump that year is the archive widening, not the weather.

By month of the year

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

From 2008 to 2025, 100% of tornado reports in Milwaukee County fell inside a tornado warning issued on average 13 minutes before, and 77% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200830100%0
200920100%0
20103167%0
201320100%0
2021110%0
2022110%3100%13 min
202410100%0

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200814750%967%38 min
20093233%4100%24 min
20108538%743%25 min
201111827%1275%23 min
201212833%1100%44 min
20137614%944%35 min
201410820%1580%14 min
20159544%1675%24 min
2016220%838%11 min
2017660%1070%19 min
20188625%475%7 min
2019330%1040%40 min
20209633%1974%13 min
20218275%560%31 min
202210100%3278%27 min
20239633%1155%20 min
202413377%1080%19 min
202518761%1560%23 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20086517%1587%135 min
20093233%888%88 min
20105420%3100%104 min
201110100%0
201310100%0
20143233%1100%42 min
20162150%250%6 min
2018110%1100%21 min
20192150%580%85 min
2020220%9100%119 min
202110100%0
2022220%683%48 min
202410100%0
20254325%667%120 min

Years from 2008, the first full year of storm-based warnings. The year still running is on its own page.

Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The latest warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Sep 4, 12:54 AM CDTSevere Thunderstorm WarningMKX51 min
Sep 4, 12:04 AM CDTSevere Thunderstorm Warning Considerable damage threatMKX56 min
Sep 3, 9:19 AM CDTFlash Flood WarningMKX2 hr
Sep 3, 7:51 AM CDTSevere Thunderstorm WarningMKX54 min
Aug 18, 6:54 PM CDTSevere Thunderstorm WarningMKX51 min
Aug 18, 6:51 PM CDTTornado WarningMKX23 min
Aug 18, 6:23 PM CDTSevere Thunderstorm WarningMKX67 min
Aug 9, 11:10 AM CDTSevere Thunderstorm WarningMKX50 min
Jul 27, 2:00 PM CDTSevere Thunderstorm WarningMKX90 min
Jul 27, 10:55 AM CDTSevere Thunderstorm WarningMKX80 min
Jul 2, 7:10 PM CDTSevere Thunderstorm WarningMKX24 min
Jun 28, 11:55 AM CDTExtreme Heat WarningMKX4 days

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive

Sources

National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.